Automobiles are a key part of modern life. They help people get to work and other places more easily than ever before. In the United States, for example, nearly three trillion miles (five trillion kilometres) are driven in passenger cars each year. New technical developments are constantly improving the body, chassis, engine, drivetrain, control systems, and safety equipment of automobiles. As a result, consumers are offered hundreds of different automobile models. The automotive industry provides many jobs, and it is one of the largest contributors to global economic growth.
The scientific and technological building blocks for the automobile go back several hundred years, but the first commercially successful car was not built until 1900. Steam, electric power and the internal combustion engine powered cars in that era. Steam engines could reach high speeds but were inefficient, and battery-powered electric cars had limited range and required a long time to recharge. The gasoline-powered automobile became the dominant type of car in the 1920s. It accelerated the expansion of cities and rural areas, brought urban amenities to rural America (including better schools and medical care), stimulated tourism and outdoor recreation, and created many related industries such as service stations and motels. It was also a major force in the development of highway construction.
In the early 20th century, Henry Ford developed methods of mass production that enabled automobile manufacturers to reduce prices and make the Model T affordable for middle-class families. In fact, the cheapest version of this one-cylinder, three-horsepower runabout sold for less than an average annual wage in 1912. Ford’s success triggered an automobile revolution that made modern life inconceivable without access to vehicles.
Today’s automobile is a complex machine with thousands of parts, arranged in semi-independent systems modeled after human body organs. The circulatory system, for example, contains systems for cooling the engine and lubricating the moving parts, while the heart of the car, the internal combustion engine, has its own system to deliver fuel and ignite it in the cylinders. The resulting explosion propels the pistons, which in turn move the wheels to generate motion.
Most modern automobiles are driven by a water-cooled, piston-type internal combustion engine that burns gasoline, but diesel engines (which burn a heavier oil) are also used. In order to keep manufacturing costs low, the automobile industry has developed a system of marketing that relies on a wide variety of makes and models for each price range, and on sharing mechanical parts between the various brands. Moreover, manufacturers have redesigned their cars frequently in order to stay competitive and attract buyers. As a result, the modern automobile is a relatively complex machine that requires considerable maintenance and repairs. This has led to the growth of a large aftermarket for auto parts, and some people even have their cars custom-built. In addition, the automobile has spawned a number of related industries, such as insurance and financing companies. In some countries, the automotive industry is heavily regulated.